KR19980080946A - Image forming apparatus and manufacturing method thereof - Google Patents

Abstract

The image forming apparatus of the present invention emits light of different colors in accordance with an electron source having a substrate on which a plurality of electron-emitting devices are arranged, and irradiation of electrons by the electron-emitting devices. It includes a front plate provided with fluorescent materials that serve to form a. Rectangular spacers are arranged between the substrate and the front plate, which are secured to the front plate and in contact with the substrate through soft members.

Description

Image forming apparatus and manufacturing method thereof

The present invention relates to an image forming apparatus having a multi-electron source and a fluorescent material and a method of manufacturing the same.

Flat display devices are thin and lightweight.

Therefore, they are attracting attention as devices replacing CRT type display devices. Display devices using a combination of electron-emitting devices and fluorescent materials that receive electron beams and emit light are expected to have better properties, in particular, than display devices based on other conventional configurations. For example, compared to the latest liquid crystal display devices, the display device is a self-emission type in that it does not require a backlight and in addition has a wide viewing angle. Better.

Typically, two types of devices, hot and cold cathode devices, are known as electron emitting devices. Known examples of cold cathode devices are surface-conduction emission type electron-emissive devices, field emission type electron emitter devices (later referred to as FE type electronic emitter devices). Mentioned), and metal / insulator / metal type electronic emitter devices (later referred to as MIM type electronic emitter devices).

Known examples of surface-conducting emission type electron emitting devices are described, for example, in M.I. Elinson, Radio Eng. Electron phys., 10, 1290 (1965) and other examples will be described later.

Surface-conducting emission type emitting devices make use of the phenomenon that electrons are emitted from a small area of thin film formed on a substrate by flowing current in parallel through the film surface. Surface-conducting emission type emitter devices are Au films [G. Dittmer, Thin Solid films, 9, 317 (1972)], In ₂ O ₃ / SnO ₂ thin films [M. Hartwell and CG Fonstad, IEEE Trans. ED Conf., 519 (1975), thin carbon films [Hisashi Araki et al., Vacuum, Vol. 26, No. 1, p. 22 (1983), and the like, and moreover, electronically emitting devices using SnO ₂ thin films according to the aforementioned Elinson.

FIG. 15 is a plan view showing a device by M. Hartwell et al. Described above as a typical example of these surface-conductive emission type emitting device structures. 15, reference numeral 3001 denotes a substrate; 3004 represents a conductive thin film made of a metal oxide formed by sputtering. This conductive thin film 3004 has an H-type pattern as shown in FIG. The electron-emitting region 3005 is formed by performing a charging process (referred to later as a forming process) on the conductive thin film. In FIG. 15 the spacing L is designated 0.5 to 1 mm and the width W is 0.1 mm. The electron-emitting region 3005 is shown in a rectangular shape at the center of the conductive thin film 3004 for convenience of description. However, this does not accurately represent the actual position and shape of the electron-emitting region.

Hartwell et al. In surface-conductive emission type emitting devices, and the like, the electron-emissive region 3005 is formed by performing a charging process, which is typically referred to as the formation of the conductive thin film 3004, before electron emission. In the formation process, for example, a DC voltage which increases at a very low rate, for example 1 V / min, is applied across both ends of the conductive thin film 3004 to partially fill the conductive thin film 3004. Or deform, thereby forming an electron-imitting region 3005 having an electrically high resistance. It is noted that the broken or deformed portion of the conductive thin film 3004 has a fixture. When an appropriate voltage is applied to the conductive thin film 3004 after the formation process, electrons are emitted near the pitcher.

Known examples of FE type e-emitting devices are described in W.P. Dyke and W.W. Dolan, Field emission, Advance in Electron Physics, 8, 89 (1956) and C.A. Spindt, Physical properties of thin-film field emission cathodes with molybdenum cones, J. Appl. Phys., 47, 5248 (1976).

FIG. 16 illustrates the above-described C.A. Sectional drawing showing a device by Spindt et al. Referring to Fig. 16, reference numeral 3010 denotes a substrate; 3011 is an emitter wiring made of a conductive material; 3012 is an emitter cone; 3013 is an insulating layer; And 3014 represents a gate electrode. In this device, a voltage is applied between emitter cone 3012 and gate electrode 3014 to emit electrons from the distal end region of emitter cone 3012. In addition to the multi-layer structure of FIG. 16, as another FE type device structure, there is an example of emitter and gate electrodes arranged on the substrate to be nearly parallel to the surface of the substrate.

Known examples of MIM type electron-emitting devices are described in C.A. Mead, Operation of Tunnel-Emission Devices, J. Appl. Phys., 32,646 (1961). 17 shows a typical example of a MIM type device structure. 17 is a sectional view of a MiM type electron-emitting device. Referring to Fig. 17, reference numeral 3020 denotes a substrate; 3021 is a lower electrode made of a metal; 3022 is a thin insulating layer having a thickness of about 100 GPa; And 3023 represents an upper electrode made of metal and having a thickness of about 80-300 kPa. In a MIM type electron-emitting device, a suitable voltage is applied between the upper electrode 3023 and the lower electrode 3021 to emit electrons from the surface of the upper electrode 3023.

The cold cathode device described above does not require any heater because it emits electrons at a lower temperature than the hot cathode device. Therefore, cold cathode devices have a simpler structure than hot cathode devices and can be micropatterned. Although many devices are arranged on a substrate at high density, problems such as cogeneration of the substrate rarely occur. In addition, the response speed of the hot cathode device is low since the device is operated by heating by the heater, while the response speed of the cold cathode device is high. For this reason, the application of cold cathode devices has been actively studied.

Among cold cathode devices, the surface-conductive emission type emitting device has an advantage because it can be easily manufactured with a simple structure. For this reason, many devices can be formed on a large area. As disclosed in Japanese Patent Laid-Open No. 64-31332 filed by the applicant, a method of arranging and driving many devices has been studied.

Multi-electronic sources and the like have been studied regarding the application of surface-conducting emission type emitting devices to image forming apparatuses such as, for example, image display apparatuses and image recording apparatuses.

As an application for an image display device, in particular, a surface-conducting emission type emitting device, as disclosed in US Pat. No. 5,066,883 and Japanese Patent Laid-Open Nos. 2-257551 and 4-28137, filed by the applicant. And an image forming apparatus using a combination of fluorescent materials that emit light upon reception of an electron beam has been studied. It is expected that this type of image forming apparatus using a combination of surface-conducting emission type emitting device and fluorescent material will have better properties than other conventional image forming apparatus. For example, compared with the latest liquid crystal display devices, the display device is a self-emition type in that it does not require a backlight and in addition has a wide viewing angle. Better.

A method of driving a plurality of FE type electron-emitting devices arranged side by side is disclosed, for example, in US Pat. No. 4,904,895 filed by the applicant. R. Meyer et al. [R. Meyer et al. Meyer: Recent Development on Microtips Display at LETI, Tech. Digest of 4th Int. Vacuum microelectronics Conf., Nagahama, pp. 6-9 (1991).

An example of applying a large number of MIM type electron-emitting devices arranged side by side in an image display apparatus is disclosed in Japanese Patent Laid-Open No. 3-55738 filed by the present applicant.

18 is a perspective view partially cut out of a display panel region as a component of a flat image display device, illustrating an internal structure of the panel.

Referring to Fig. 18, reference numeral 3115 denotes a rear plate; 3116 is a sidewall; And 3117 represents a face plate. The back plate 3115, sidewalls 3116, and front plate 3117 are configured as envelopes (closed containers) for maintaining a vacuum in the display panel.

The back plate 3115 has a substrate 3111 fixed thereon, on which N × M cold cathode devices 3112 are formed (M and N are positive integers of 2 or more, suitably Is specified according to the desired number of display pixels). The N × M cold cathode devices 3112 are arranged in a matrix of M row-directional wires 3113 and N column-directional wires 3114. The region composed of the substrate 3111, cold cathode devices 3112, column-directional wirings 3113, and row-directional wirings 3114 will be referred to as a multi-electronic source. An insulating layer, not shown, is formed between each column-direction wiring 3113 and each row-direction wiring 3114 in a region at least perpendicularly intersecting with each other to maintain electrical insulation therebetween.

A fluorescent film 3118 made of a fluorescent material is formed on the lower surface of the front plate 3117. The fluorescent film 3118 is coated with red (R), green (G), and blue (B) fluorescent materials (not shown), that is, three primary fluorescent materials. Black conductive members (not shown) are provided between each color fluorescent material of the fluorescent film 3118. A metal rear surface 3119 made of aluminum (Al) or the like is formed on the surface of the fluorescent film 3118 to be positioned toward the rear plate 3115. Reference numerals Dx1 to DxM, Dy1 to DyN and Hv denote electrical connection terminals for a sealed structure provided to electrically connect the display panel to an electrical circuit (not shown). The terminals Dx1 to DxM are electrically connected to the column-directional wirings 3113 of the multi-electronic source; Terminals Dy1 to DyN are connected to the row-directional wiring 3114; And the terminal Hv is connected to the metal back surface 3119 of the front plate.

A vacuum of about 10 ⁻⁶ Torr is maintained in the closed vessel. As the display area of the image display device increases, the device needs a means to prevent the back plate 3115 and the front plate 3117 from being deformed or destroyed by the pressure difference between the inside and outside of the sealed container. . The thickening of the back plate 3115 and the front plate 3117 will increase the weight of the image display device and cause image distortion or parallax when the display screen is viewed at an angle. In contrast, the structure shown in FIG. 18 includes structural support members (called spacers or ribs) formed from relatively thin glass plates and used to withstand atmospheric pressure. With this structure, spacing of not more than millimeters or several millimeters is generally secured between the substrate on which the multi-electron source is formed and the front plate 3117 on which the fluorescent film 3118 is formed, and as described above, in a sealed container. High vacuum is maintained.

In the image display apparatus using the display panel, when a voltage is applied to each cold cathode device 3112 through the external terminals Dx1 to DxM and Dy1 to DyN, electrons are emitted by the cold cathode device 3112. At the same time, a high voltage of hundreds to thousands of KV is applied to the metal backside 3119 through the external terminal Hv to accelerate the emitted electrons so that the electrons collide with the inner surface of the front plate 3117. In this operation, each color fluorescent material constituting the fluorescent film 3118 is excited to emit light. As a result, the image is displayed on the screen.

The following problems are raised in the display panel of the image display apparatus described above.

The spacers 3120 arranged in the image display apparatus should be sufficiently disposed and assembled with respect to the substrate 3111 and the front plate 3117. In particular, the spacers 3120 should be sufficiently disposed with respect to the fluorescent film 3118 on the side of the front plate 3117 so as not to destroy the display pixel by the spacers. Otherwise, the quality of the displayed image may be degraded.

If the spacer 3120 is not securely arranged to the image display device, the spacer may be moved or dropped greatly and may be damaged due to external impact on the panel during or after assembling the sealed container.

The present invention has been made in view of the above prior art, and has an important object to provide an image forming apparatus having spacers securely fixed inside the apparatus.

It is a further object of the present invention to provide an image forming apparatus having a spacer which is only adjacent on a member facing the image forming member and fixed on the image forming member and spaces securely fixed inside the apparatus.

It is yet another object of the present invention to provide a method of manufacturing an image forming apparatus that can facilitate the arrangement of spacers in the assembly of the image forming apparatus.

Other features and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like letters indicate like or similar parts throughout the drawings.

1 is a cross-sectional view taken along line A-A 'of a display panel (Figure 2) according to an embodiment of the invention.

2 is a perspective view partially cut away of a display panel of the image display apparatus according to the present embodiment;

3 is a plan view showing a portion of a multi-electron source substrate used in this embodiment.

4 is a cross-sectional view showing a portion of a multi-electron source substrate used in this embodiment.

5A and 5B are plan views showing examples of arrangement of fluorescent materials on a front plate of a display panel according to the present embodiment;

6 is a plan view showing another example of the arrangement of the fluorescent material on the front plate of the display panel according to the present embodiment;

7A and 7B are a plan view and a sectional view, respectively, of a flat surface-conductive emission type emitting device according to the present embodiment;

8A to 8E are cross-sectional views showing manufacturing steps of the flat surface-conductive emission type emitting device according to the present embodiment.

9 is a graph showing waveforms of an applied voltage in a forming process.

10A to 10B are graphs respectively showing waveforms of applied voltages and changes in the emission current Ie in the activation process.

Fig. 11 is a sectional view showing a step surface-conductive emission type emitting device used in this embodiment.

12A-12F are cross-sectional views illustrating steps of fabricating a step surface-conductive emission type emitting device.

Fig. 13 is a graph showing typical characteristics of the surface-conductive emission type emitting device used in this embodiment.

Fig. 14 is a block diagram showing a schematic arrangement of a driving circuit for the image forming apparatus according to the embodiment of the present invention.

15 is a plan view showing an example of a known conventional surface-conductive emission type emitting device.

Fig. 16 is a sectional view showing an example of a known conventional FE type device.

Fig. 17 is a sectional view showing an example of a known conventional MIM type device.

18 is a perspective view partially cut away from a display panel of the image display device;

19 and 20 are diagrams for explaining stress concentration points and relaxation of stress.

Explanation of symbols for the main parts of the drawings

3a, 3b: joint surface

11: high-resistance film

21a, 21b: low-resistance film

23: protective film

31: binding substance

1017: front plate

1011: Substrate

1012 cold cathode device

1015: back plate

1020: spacer

1018: fluorescent film

1019: metal back

The image forming apparatus according to the present invention includes spacers positioned between the image forming member and the member facing the image forming member. The spacer is fixed to the image forming member and in contact with the member facing the image forming member.

In the manufacturing method of the image forming apparatus according to the present invention, the spacer located between the image forming member and the member facing the image forming member is first fixed to the image forming member and brought into contact with the member facing the image forming member.

In the present invention, it is preferred that the spacer is in contact with the member facing the image forming member through a soft member. The flexible member is softer than the base material of the spacer and the material of the member facing the image forming member to which the spacer is in contact.

The base material of the spacer can be a glass material or a ceramic material as described later. The softer of the glass materials has a Vickers hardness of about 500. The material of the member facing the image forming member may be a printed wiring (silver paste with Ag and glass components printed and burned) on a substrate of a multi-electronic source (as described later). The Vicker hardness of the printed wiring is about the same or smaller than that of the glass material. Therefore, the Vickers hardness of the soft material to effectively achieve the effects of the present invention is about 200 or less than 100. For example, parts of precious metals such as Au, Pt, Pd, Rh and Ag or metal alloys such as Cu have a Vicker hardness of less than 50, and these materials are preferred as materials with soft materials.

In the present invention, the spacer includes both insulating spacers and conductive spacers. For example, in the image forming apparatus shown in FIG. 18, the following points should be considered.

First, when some of the electrons emitted from the area near the spacer 3120 collide with the spacer 3120, or when ions generated due to the emitted electron effect are attached to the spacer 3120, the spacer 3120 ) Can be charged. Moreover, if any electrons reaching the front plate 3117 are reflected and scattered by the front plate 3117 and any scattered electrons collide with the spacer 3120, the spacer 3120 may be charged. . If the spacer 3120 is charged in this manner, the trajectory of the electrons emitted by the cold cathode devices 3112 is skewed. As a result, the electrons reach an inappropriate location on the fluorescent material and a distorted image is displayed near the spacer 3120.

Second, in order to accelerate the electrons emitted by the cold cathode device 3112, several hundred volts (V) or more high voltage (i.e., 1 kV / mm or more high field) is applied to the front plate 3117 and multiply. Since it is applied between electron sources, a discharge may occur at the surface of the spacer 3120. In particular, when the spacer 3120 is charged as in the above case, in particular, a discharge can be induced.

In view of the above, a spacer having a good insulating property sufficient to withstand a high applied voltage and having a conductive surface capable of alleviating the state of charge is preferably used in the present invention, to suppress the deviation of the electron beam and near the spacer. Discharge at

According to the invention, when the conductive spacers are arranged, the spacers are preferably electrically connected to the conductive members arranged on the image forming member and the conductive members arranged on the member facing the image forming member. In this arrangement, the charging of the spacer can be removed by flowing a small current through the spacer.

For example, the member facing the image forming member is a substrate on which a plurality of electronic imaging devices are arranged, and the spacer is fixed with a conductive adhesive to the substrate on which the electronic imaging device is arranged, which prevents the adhesive from being detached. Should be. The reason is that the adhesive pressed on the substrate on which the electron emitting device is arranged can disturb the electric field near the spacer and can affect the electron trajectory emitted by the electron-imitting device near the spacer. However, in the present invention, since the spacer is simply in contact with the member facing the image forming member and is not fixed to the member facing the image forming member with an adhesive or the like, the influence on the orbit of the emitted electrons must be considered. There is no.

In the present invention, when the conductive spacers are arranged, the flexible member is made of a noble metal material (to be described later). Contact of the spacer through the ductile metal and the member facing the image forming member can improve the electrical connection.

In the present invention, the electron source includes an electron source having cold cathode devices or hot cathode devices. Electronic sources having such cold cathode devices, such as surface-conductive emission type emitting devices, FE type devices, MIM type devices, and the like, are preferably used in the present invention. In particular, an electron source having a surface-conducting emission type emitting device is more preferably used in the present invention.

Since the cold cathode device described above can emit electrons at a lower temperature than that for a hot cathode device, no heater is required. Therefore, the cold cathode device can be finely patterned with a simpler structure than that of the hot cathode device. Even if a large number of devices are arranged at a high density on the substrate, such problems such as thermal merging of the substrates rarely occur. In addition, while the response speed of the cold cathode device is high, the response speed of the hot cathode device is low because it operates during heating by the heater.

For example, a surface-conductive emission type emitting device among all cold cathode devices can be easily manufactured, especially with a simple structure and such a large number of devices can be formed over a large area.

According to the invention, each spacer is preferably fixed to the image forming member by bonding the spacer to the image forming member. For example, the space may be bonded to the image forming member with a bonding material such as melt glass that dissolves upon application of heat.

The image forming apparatus of the present invention has the following form.

(1) The electrodes are arranged on the image forming member. This electrode is an acceleration electrode for accelerating electrons emitted by the electron source. In an image forming apparatus, an image is formed by irradiating electrons emitted by an electron source onto an image forming member in accordance with an input signal. In the image forming apparatus, the image forming member is especially a fluorescent material.

(2) An electron source is an electron source having a simple matrix layout in which a plurality of electron-emitting devices are wired in a matrix by a plurality of column-direction wirings and a plurality of row-direction wirings.

(3) electron sources are ladder-like electron sources arranged in parallel and arranged in a plurality of rows of a plurality of electron-emissive devices (hereinafter referred to as column directions) which are connected at two terminals of each device. Control electrodes arranged along a direction perpendicular to these ladder wire control electrodes emitted by the direction perpendicular to these ladder wires (hereinafter referred to as row direction) above the electro-emitting devices. (Hereinafter referred to as a grid) controls the electrons emitted by the electron-emitting devices.

(4) According to the concept of the present invention, the image forming apparatus is not limited to the image forming apparatus suitable for the display. The image forming apparatus mentioned above may also be used as a light-emitting source for an optical printer made of a photoelectric drum, a light-emitting diode, and the like instead of a light-emitting diode. At this time, by appropriately selecting the M column-direction wiring and the N row-direction wiring, the image forming apparatus can be applied as a two-dimensional light-emitting device as well as a linear light-emitting source. In this case, the image forming member is not limited to a material which emits light directly, such as a fluorescent material used in the embodiment (to be described below), and may be a member in which a hidden image is formed by charging electrons. .

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As a feature of an embodiment of the invention, the structure of the spacers and the method of assembling the device will be described.

1 is a partial cross-sectional view of a display panel showing a characteristic portion of an image display apparatus according to an embodiment. 2 is a diagram schematically illustrating a structure of a display panel (described in detail below). 1 illustrates a phosphor film facing each other through a substrate 1011 and a spacer 1020 having a plurality of cold cathode devices 1012 along a line A-A 'and acting as a film of light-emitting material ( A cross section of a display panel having a transparent front plate 1017 structure with 1018 is shown.

The spacer 1020 is formed by forming a high-resistance film 11 on the surface of the insulating member 1 to prevent charging and bonding of the spacers facing the inner surface of the front plate 1017 and the surface of the substrate 1011, respectively. It is constructed by forming the low-resistance films 21a and 22b on the surfaces 3a and 3b. The spacer 1020 is fixed only to the inner surface of the front plate 1017 through the conductive bonding material 31. Then, the front plate 1017 and the substrate 1011 are assembled as a display panel. Accordingly, the high-resistance film 11 of the spacer is formed on the inner surface of the front plate 1017 via the low-resistance film 21a and the bonding material 31, and the low-resistance film. It is electrically connected to the column-directional wiring 1013 formed on the substrate 1011 via 21b.

In order to prevent the binding material 31 from directly contacting the high-resistance film 11, a protective film (or a film on the side surface of the spacer 1020 in contact with the bonding surface 3a on the front plate 1017 side of the spacer 1020) may be used. 23) is formed. The protective film 23 is preferably made of a material having a low reactivity with respect to the bonding material 31. The low-resistance film 21a also functions as a protective film by making the material film 21a having a low reactivity with respect to the bonding material 31.

In such a display panel, the low-resistance film 21b of the spacer 1020 on the side of the substrate 1011 on which the cold cathode device emitting electrons is formed is formed only on the bonding surface 3b on the side of the substrate 1011. The potential distribution near the substrate 1011 remains unchanged as compared with the case where no spacer 1020 is arranged. Therefore, the electron trajectory emitted by the cold cathode device 1012 near the spacer 1020 does not change.

The mechanical or chemical effect on the high-resistance film 11 in fixing the spacer 1020 to the front plate 1017 side through the binding material 31 is due to the front plate 1017 side where the accelerated electrons collide. It can be avoided by the protective film 23 formed on the side surface which contacts the facing joint surface 3a. In particular, the high-resistance of the three films, the high-resistance film 11 and the low-resistance film 21a, and the bonding material 31 (more, four films including the insulating member 1) in contact with each other. At the bonding portion between the film 11 and the low-resistance film 21a, a chemical reaction easily occurs during a process such as heating in the manufacture of the display panel. Therefore, it is important to avoid the effect on the joint. When the protective film 23 is formed of the extended low-resistance film 21a, the potential distribution may be distorted by the protective film 23 near the front plate 1017. However, the electrons emitted by the cold cathode device 1012 are accelerated to a very large extent near the front plate 1017, so that the effect of distortion on the potential distribution on the trajectories of the electrons is negligible.

The arrangement of the display panel of the image forming apparatus and the manufacturing method thereof according to the present embodiment will be described in detail.

2 is a perspective view partially cut out of a part of the display panel used in the present embodiment, showing the internal structure of the display panel.

2, reference numeral 1015 denotes a rear plate; 1016 represents a sidewall; And 1017 represents a face plate. These parts constitute a closed container that maintains a vacuum inside the display panel. In order to make a sealed container, it is necessary to seal the individual parts to keep the sealed state to obtain sufficient strength. For example, molten glass is supplied to the bonded portion and sintered in the atmosphere or in a nitrogen atmosphere of 400 to 500 ° C., and the portions are sealed. The method of evacuating air from inside the vessel will be described later. In addition, since a vacuum of about 10 ⁻⁶ Torr is maintained in the closed vessel, the spacers 1020 are arranged as a structure that resists atmospheric pressure to prevent the sealed vessel from being destroyed by atmospheric pressure or unexpected impact.

The back plate 1015 has a substrate 1011 fixed thereto, on which N x M cold cathode devices 1012 are formed (M and N = 2 or more positive integers, suitably the display). Specified according to the number of pixels, for example in a display device for a high-resolution TV display, preferably N = 3,000 or more, M = 1,000 or more). N × M cold cathode devices are arranged in a simple matrix of M row-directional wires 1013 and N column-directional wires 1014. The portion consisting of the components indicated by reference numerals 1011 to 1014 will be referred to as a multi electron source.

If the multi-electron source used in the image display apparatus according to the present embodiment is an electron source constituted by a cold cathode device arranged in a simple matrix, the material and shape of each cold cathode device and its manufacturing method are not particularly limited. Thus, for example, cold cathode devices such as surface-conductive emission type emitting device, FE type devices, or MIM type devices may be used.

Next, the structure of a multi-electron source having surface-conductive emission type emitting device (to be described later) arranged as a cold cathode device on a substrate using wiring will be described below.

3 is a plan view of a multi-electronic source used in the display panel of FIG. 2. On the substrate 1011 are surface-conductive emission type emitting devices such as those shown in FIGS. 7A and 7B. These devices are arranged in a simple matrix using column-direction wiring 1013 and row-direction wiring 1014. At the intersection of the wirings 1013 and 1014, an insulating layer (not shown) is formed between the wirings to maintain electrical insulation.

4 is a cross-sectional view taken along the line BB ′ of FIG. 3.

A multi-electron source having such a structure forms column- and row-direction wires 1013 and 1014, inter-electrode insulating layers (not shown), and device electrodes and conductive thin films on the substrate, and then the column Note that it has a structure manufactured by supplying electricity to the respective devices through the row-direction wirings 1013 and 1014 to perform a formation process to be described later and an activation process to be described later.

In this embodiment, the substrate 1011 of the multi-electron source is fixed to the back plate 1015 of the sealed container. However, if the substrate 1011 of the multi-electron source has sufficient strength, the substrate 1011 of the multi-electron source may also serve as the back plate of the sealed container.

The fluorescent film 1018 is formed on the lower surface of the front plate 1017. Since the present embodiment is a color display device, the fluorescent film 1018 is coated with red, green, and blue fluorescent materials, that is, three primary fluorescent materials. As shown in FIG. 5A, each of the color fluorescent materials is formed in a stripe structure, and a black conductive member 1010 is provided between the stripes of the fluorescent materials. The purpose of providing this black conductive member is to prevent display color misregistration even if the electron-beam irradiation position is shifted to some extent, to prevent display degradation by blocking reflection of external light, and to prevent electron beam It is to prevent the charging of the fluorescent film by. As the material of the black conductive member 1010, graphite is used as the main component, but other materials may be used as long as the above object can be achieved.

Moreover, the trichromatic fluorescent film is not limited to the stripes as shown in Fig. 5A. For example, a delta arrangement or other arrangement as shown in FIG. 5B may be used. For example, as shown in Fig. 6, the black conductive members 1010 are perpendicular to the stripes as well as between the stripes of the respective colors of the fluorescent film to separate the pixels in the column and row directions. It can be formed as. Note that when a monochromatic display panel is formed, a monochromatic fluorescent substance can be applied to the fluorescent film and the black conductive member can be omitted.

Furthermore, a metal backside 1019 known in the CRT field is provided on the fluorescent film 1018 toward the back plate 1019 side. The purpose of providing a metal backside 1019 is to be a mirror-reflective portion of the light emitted by the fluorescent film 1018 to improve light-utility, to protect the fluorescent film 1018 from colliding with anions, and It is intended to be used as an electrode for supplying a beam acceleration voltage, and to be used as a conductive path for electrons excited by the fluorescent film 1018. The metal backside 1019 is formed by forming a fluorescent film 1018 on the front plate 1017, smoothing the entire surface of the fluorescent film, and depositing aluminum thereon by vacuum deposition thereon. Note that when the low voltage fluorescent material is used for the fluorescent film 1018, the metal backside 1019 is not used.

In addition, for the application of an acceleration voltage or to improve the conductivity of the fluorescent film, transparent electrodes made of, for example, ITO are provided between the front plate 1017 and the fluorescent film 1018, although such electrodes are not used in this embodiment. Can be.

In the closure of the container described above, the back plate 1015, the front plate 1017, and the spacer 1020 are formed of fluorescent materials of respective colors arranged on the front plate and devices arranged on the substrate 1011. It should be arranged enough to correspond with each other.

1 is a schematic cross-sectional view of a display panel taken along a line A-A 'of FIG. 2. Like reference numerals in FIG. 1 denote like parts in FIG. 2.

Each spacer 1020 forms a high-resistance film 11 on the surface of the insulating member 1 to prevent electrification, the inner surface of the front plate 1017 (metal back surface 1019, etc.) and the substrate 1011. Low-resistance films 21a and 22b are formed on the bonding surfaces 3a and 3b of the spacer 1020 facing the surface of the (column- or row-directional wiring 1013 or 1014) and the bonding surface 3a. It is a member obtained by forming the protective film 23 on the side surface of the spacer 1020 on the side. The required number of spacers 1020 are secured to the inner surface of the front plate 1017 at the required spacing from the bonding material 31 to achieve this purpose. In addition, the high-resistance films 11 are formed of surfaces having at least the surface of the insulating member 1 exposed to the vacuum in the sealed container. The high-resistance film 11 is connected to the inner surface of the front plate 1017 (such as the metal backside 1019) and the spacer 1020 through the low-resistance film 21a and the coupling material 31 on the spacer 1020. Is electrically connected to the surface of the substrate 1011 (column- or row-directional wiring 1013 or 1014) via the low-resistance film 21b on the surface. In this embodiment, the spacers 1020 are thin flat. ) And extend at the same interval as the corresponding column-directional wirings 1013 and are electrically connected thereto.

The spacer 1020 has an insulating property sufficient to withstand the high voltage applied between the column- and row-direction wirings 1013 and 1014 on the substrate 1011 and the metal backside on the inner surface of the front plate 1017. It has sufficient conductivity to prevent the surface of the spacer from filling up.

As the insulating member of the spacer 1020, for example, a ceramic member composed of a silica glass member, a glass member containing a small amount of impurities such as Na, a soda-lime glass member, an alumina, or the like may be used. useful. The insulating member 1 preferably has a coefficient of thermal expansion close to that of the hermetic container and the substrate 1011.

The current obtained by dividing the acceleration voltage applied in the high potential to the front plate 1017 (such as the metal backside 1019) by the resistance Rs of the high-resistance film 11 is a high-resistance constituting the spacer 1020. Flow in the membrane (11). The resistance Rs of the spacer 1020 is set within a desired range in terms of preventing charging and power consumption. The sheet resistance R (µs / sq) is set at 10 ¹² µs / sq or less from the viewpoint of preventing charging. In order to obtain a sufficient antistatic effect, the sheet resistance R is preferably set at 10 ¹¹ kPa / sq or less. The lower limit of the sheet resistance depends on the shape of each spacer 1020 and the voltage applied between the spacers 1020, and is preferably set at 10 ⁵ mA / sq or more.

The thickness of the high-resistance film 11 formed on the insulating member 1 is preferably in the range of 10 nm to 1 mu m. Thin films having a thickness of 10 nm or less are generally formed in an island shape and exhibit unstable resistance depending on the surface energy of the material, the adhesion properties with the substrate, and the substrate temperature, resulting in poor regeneration characteristics. On the contrary, if the thickness t is 1 탆 or more, the stress of the film is increased and the possibility of peeling of the film is increased. In addition, longer cycle times are required to form the film, resulting in poor productivity. The thickness of the high-resistance film 11 is preferably in the range of 50 to 500 nm. The sheet resistance R (Ω / sq) is ρ / t, and the resistivity ρ of the high-resistance film 11 is preferably 0.1 Ωcm to 10 in consideration of the preferred range of the sheet resistance R (Ω / sq) and the thickness t. ^It is in the range of ⁸ cm. In order to specify the sheet resistance and the film thickness in a more preferable range, the specific resistivity p is preferably set to 10 ² to 10 ⁶ kcm.

As described above, when a current flows in the high-resistance film 11 formed on the insulating member 1 or when the entire display generates heat during operation, the temperature of each spacer 1020 rises. If the resistance temper coefficient of the high-resistance film 11 is a large negative value, the resistance decreases with increasing temperature. As a result, the current flowing through the spacer 1020 increases to increase the temperature. The current increases beyond the limit of the power supply. It is empirically known that the resistance temperature coefficient causing such an excessive increase in current is a negative value with an absolute value of 1% or more. That is, when having a negative value, the resistance temperature coefficient of the absolute value of the high-resistance film is preferably set to less than -1%.

As a material for the high-resistance film 11 having antistatic properties in the spacer 1020, for example, metal oxide is used. Metal oxide is preferably chromium oxide, nickel oxide, or copper oxide. This is because among these oxides have a relatively low secondary electron-emitting efficiency and electrons emitted by the cold cathode device 1012 are not easily charged even if they collide with the spacer 1020. Besides such metal oxides, carbon materials are preferably used because they have a low secondary electron-emitting efficiency. Since the amorphous carbon material has a high resistance, the resistance of the spacer 1020 can be easily controlled to a desired value.

Aluminum-transition metal alloy nitride is another material for the high-resistance film 11 having antistatic properties because it can be controlled in a wide range of resistances from the resistance of a good conductor to the resistance of an insulator by adjusting the composition of the transition metal. desirable. This nitride is a stable material whose resistance only changes slightly in the manufacturing process of the display device (to be described later). In addition, these materials have a resistive temperature coefficient of less than -1% and can therefore be useful in practice. As the transition metal element, Ti, Cr, Ta, and the like are useful.

The alloy nitride film is formed on the insulating member 1 by such thin film forming means as sputtering, reactive sputtering in a nitrogen atmosphere, electron beam deposition, ion plating, or ion-assisted deposition. The metal oxide film is formed by the same thin film formation method except that oxygen is used instead of nitrogen. Such metal oxide films may also be formed by CVD or alkali oxide application. The carbon film is formed by deposition, sputtering, CVD, or plasma CVD. When the amorphous film is formed, in particular, hydrogen is contained in the atmosphere in the film forming process, or hydrogen gas is used as the film forming gas.

The low-resistance films 21a and 21b of the spacer 1020 allow the high-resistance film 11 to be placed on the front plate 1017 (such as the metal back surface 1019, etc.) on the high potential side and the substrate 1011 on the low-potential side. (Column- and row-directional wirings 1013 and 1014, etc.). The low-resistance films 21 and 22 will also be referred to later as an intermediate electrode layer (intermediate layer). The middle electrode layers (middle layers) have a number of functions as described below.

(1) The low-resistance films serve to electrically connect the high-resistance films 11 to the front plate 1017 and the substrate 1011. As described above, high-resistance films are formed to prevent the surface of the spacer 1020 from filling. However, the high-resistance film 11 is connected directly to the front plate 1017 (such as the metal backside 1019) and the substrate 1011 (such as the wirings 1013 and 1014) or through the bonding material 31. In this case, a large contact resistance is generated at the interface between the connecting portions. As a result, the charges generated on the surface of the spacer 1020 are removed. To prevent this, low-resistance interlayers 21a and 21b are formed on the bonding surface or side portions in contact with the bonding surface of the spacer 1020, and the front plate 1017, the substrate 1011 and the bonding material ( 31).

(2) The low-resistance film serves to make the potential distribution of the high-resistance films 11 uniform.

The electrons emitted by the cold cathode device 1012 follow the trajectories formed according to the potential distribution formed between the front plate 1017 and the substrate 1011. In order to prevent electron trajectories from being disturbed near the spacers 1020, the overall potential distributions of the spacers 1020 must be controlled. The high-resistance films 11 are connected directly to the front plate 1017 (such as the metal backside 1019) and the substrate 1011 (such as the wirings 1013 and 1014) or through the bonding material 31. However, due to the contact resistance at the interface, various connection states occur between the connecting parts. As a result, the potential distribution of each high-resistance film can deviate from a desired value. To prevent this, low-resistance interlayers 21a and 21b are formed along the front plate 1017 and the entire length of the spacer (side portion in contact with the adjacent or adjacent surface) in contact with the substrate. By applying a desired potential to each intermediate layer portion, the total potential of each high-resistance film 11 can be controlled.

As the material for the low-resistance films 21a and 21b, a material having a resistance sufficiently lower than that of the high-resistance film 11 can be selected. For example, such materials include Ni, Cr, Au, Mo, W, Pt, Ti, Al, Cu, and Pd, alloys of such, Pd, Ag, Au, RuO ₂ , and Pd-Ag or metal oxides and Suitably selected from printed conductors composed of metals such as glass and the like, transparent conductors such as In ₂ O ₃ -SnO ₂ , and semiconductor materials such as polysilicon.

One of the preferred conditions for the material of the low-resistance films 21a and 21b is to heat-treat and seal with molten glass in the manufacture of the image forming apparatus of this embodiment without increasing the resistance when the material changes, such as oxidation or solidification. It has characteristics that do not cause any incomplete charging to the bonding portion having the high-resistance film 11 during. In this respect, as a preferable material for the low-resistance films 21a and 21b, a noble metal, for example, platinum is particularly useful. In this case, the low-resistance film 21a made of the noble metal is made of a metal material such as Ti, Cr, or Ta in order to have satisfactory fixation properties with respect to the insulating member 1 or the high-resistance film 11. It is preferably formed through a layer having a thickness of several nm to several tens nm. This layer is called the base layer.

The thicknesses of the low-resistance films 21a and 21b are preferably in the range of 10 nm to 1 mu m. Thin films having a thickness of 10 nm or less are generally formed like islands and exhibit unstable resistance, resulting in poor regeneration. In contrast, if the thickness is 1 μm or more, the film stress increases and the likelihood of the film peeling increases. In addition, longer periods of time are required to form the film, resulting in poor productivity. The thickness of the low-resistance films 21a and 21b is preferably in the range of 50 to 500 nm.

As described above, the low-resistance film 21a formed to connect the high-resistance film 11 to the high-potential side front plate (metal back face 1019, etc.) is preferably used for the bonding material 31. Made of material with low reactivity. Also in this case, the low-resistance film 21a is preferably obtained by forming a noble metal film such as a platinum film on the uppermost surface of the spacer.

Preferred materials for the protective film 23 are materials having a low reactivity with respect to the binding material 31 and do not allow components of the binding material 31 to penetrate therein. For example, as a material for the protective film 23, a noble metal such as platinum may be used similarly to the low-resistance film 21a. In this case, the low-resistance film 21a and the protective film 23 can be formed simultaneously as the same member. As the protective film 23 material, very stable oxides such as AI ₂ O _3, SiO _2, and Ta ₂ O ₅ or nitrides such as Si ₃ N ₄ may be used. When such an oxide or nitride is used for the protective film 23, the resistance of the protective film 23 is very high, so as to prevent charging and discharging as long as the bonding materials 11 and the high-resistance film 11 are not in contact with each other. From the viewpoint, the exposed area of the protective film is specified as small as possible.

With respect to the adjacent portion of the spacer 1020 to the substrate 1011 (wiring 1013 or 1014, etc.), because the spacer 1020 is adjacent to the column- or row-direction wiring 1013 or 1014 at atmospheric pressure, Situations such as this are preferably considered. In particular, the column- and row-direction wirings 1013 and 1014 are formed to a thickness of 1 mm or more by another method of crossing each other through a printing or insulating layer (not shown), and the corrugation of the column and row-direction wirings When formed in the folds between 1013 and 1014, the following situational points become very effective because stress tends to be concentrated locally.

In order to prevent damage to the spacers 1020, the column- and row-direction wirings 1013 and 1014 due to the concentration of stress, the material for the low-resistance film 21b is formed by the wirings for contacting the spacers and the spacers ( Preference is given to materials that are softer than the materials making up the column- or row-directional wiring).

19 and 20 are views for explaining the effect of mitigating stress contact in assembling the spacer 10200, fixing it to the front plate 1017, and making contact with the substrate 1011 side (wiring 1013 or 1014, etc.). 1 is the same as FIG. 1, and shows a cross-sectional view taken along the line A-A 'in FIG. 2, and FIG. 20 shows a cross-sectional view taken along the line C-C' in FIG. 2.

In FIG. 19, one of the parts where stress is easily concentrated is the edge portion A at the boundary between the bonding surface 3b of the spacer 1020 and the side portion 5 of the spacer 1020 on the substrate 1011 side. By covering the edge portion A with the low-resistance film 21b made of a soft material, stress can be alleviated to prevent damage to the spacer 1020.

In FIG. 20, the column-direction wiring 1013 has a shape protruding to a portion where the row-direction wiring 1014 and the insulating layer 1099 are present. Among the junction points in contact with the spacers 1020, the protruding end portion (B) is also a portion where stress is easily concentrated. By covering the end portion (B portion) protruding with the low-resistance film 21b made of a soft material, stress can be alleviated to prevent damage to the spacer 1020.

In the embodiment shown in FIGS. 1 and 2, the low-resistance film 21b is softer than the material constituting the insulating member 1 serving as the substrate of the spacer 1020 and the material constituting the wiring 1013. Made of material Such soft materials used for the low-resistance film 21b are preferably noble metals based on platinum such as Pt, Pd, Rh, noble metals such as Au or Ag, or alloys of noble metals. As elastic systems, gold systems, platinum systems, and alloy systems of silver and copper are particularly useful. Other metals or alloys may be used as the soft material, but the materials described above are more preferred.

The bonding material 31 needs to have a satisfactory conductivity for electrically connecting the spacers 1020 to the metal backside 1019 of the front plate 1017. For example, a conductive molten glass including a conductive adhesive or a metal particle or a conductive filler (ceramic particle having conductive surfaces by metal plating) is suitably used.

The external terminals Dx1 to DxM, Dy1 to DyN, and Hv of the display panel are electrical connection terminals provided for the sealed structure to electrically connect the display panel to an electrical circuit not shown. Terminals Dx1 to DxM are connected to the column-directional wires 1013 of the multi-electronic source; Terminals Dy1 to DyN are connected to the row-direction wirings 1014; And the terminal Hv are electrically connected to the metal rear surface 1019 of the front plate.

To empty the sealed container, after forming the sealed container, an exhaust pipe and a vacuum pump (both not shown) are connected and the sealed container is emptied to a vacuum of about 10 ^-7 Torr. After that, the exhaust pipe is sealed. In order to maintain the vacuum in a hermetically sealed container, a getter film (not shown) is formed at a predetermined position in the hermetically sealed container immediately before / after sealing. The getter film is a film formed by heating and depositing, heating or RF heating, for example, a getter material composed mainly of Ba. The suction effect of the getter film maintains a vacuum of 1 × 10 ⁻⁵ or 1 × 10 ⁻⁷ Torr in the vessel.

In the image display apparatus using the display panel, when voltages are applied to the cold cathode device 1012 through the external terminals Dx1 to DxM and Dy1 to DyN, electrons are emitted by the cold cathode devices. At the same time, a high voltage of several hundred volts to several thousand volts is applied to the metal backside 1019 through the external terminal Hv and accelerated so that the emitted electrons collide with the inner surface of the front plate 1017. In this operation, each color fluorescent material constituting the fluorescent film 1018 is excited to emit light to display an image.

In the embodiment of the present invention, the voltage to be applied to each surface-conductive emission type emitting device 1012 that is a cold cathode device is typically designated about 12 to 16 V; The distance d between the metal backside 1019 and the cold cathode device 1012 is between about 0.1 mm and 8 mm; And the voltage applied between the metal backside 1019 and the cold cathode device 1012 is specified as about 0.1 kV to 10 kV.

In the above, the basic arrangement of the display panel, the manufacturing method thereof, and the image display apparatus according to the embodiment of the present invention have been briefly described.

Manufacturing method of multi electron source

The manufacturing method of the multi-electronic source used for the display panel of this embodiment will be described below. In the manufacture of the multi-electronic source used in the image display apparatus of this embodiment, any for each surface-conduction emission type emitting device, as long as the electron source can be obtained by arranging the cold cathode devices in a simple matrix form. Materials, shapes, and methods of manufacture can be used. Therefore, cold cathode devices such as surface-conducting emission type emitting devices, FE type devices, or MIM type devices can be used.

Under circumstances where a low cost display device with a large display area is required, of these cold cathode devices, a surface-conducting emission type emitting device is particularly preferred. More specifically, the electron-emissive properties of FE type devices are greatly influenced by the relative positions and shapes of the emitter cone and gate electrode, and thus high-precision to manufacture this device. Manufacturing skills are required. This also causes disadvantages in achieving a wide display area and low manufacturing cost. According to the MIM type device, the thicknesses of the insulating layer and the top electrode should be reduced and uniform. This also causes a big factor in achieving a wide display area and low cost. In contrast, the surface conduction emission type emitting device can be manufactured by a relatively simple manufacturing method, so that an increase in display area and a reduction in manufacturing cost can be achieved. The inventors also found that, among the surface conduction emission type emitting devices, an electron-emitting device having its peripheral region composed of an electron-emissive portion or a fine particle film can be manufactured excellent and easily in electron-emitting properties. Found. Such a device can therefore be best used for the multi-electronic sources of high-brightness, wide-screen image display devices. For this reason, in the display panel of the present embodiment, surface-conducting emission type emitting devices each having an electron emitting portion or a peripheral portion thereof made of a fine particle film are used. The basic structure, manufacturing method, and properties of the preferred surface-conducting emission type emitting device will first be described. The structure of a multi-electronic source with many devices wired in a simple matrix form will be described later.

Structure and Preferred Manufacturing Method of Preferred Surface-Conducting Emission Type Emitting Devices

Typical examples of surface-conducting emission type emitting devices, each having its peripheral area of an electron-emissive portion or a fine particle film, are two types of devices: flat and step types. Include them.

Flat surface-conduction emission type emitter device

First, the structure and fabrication method of a flat surface-conducting emission type emitting device will be described.

7A and 7B are a plan view and a cross-sectional view for explaining the structure of a flat surface-conducting emission type emitting device, respectively.

7A and 7B, reference numeral 1101 denotes a substrate; 1102 and 1103 represent device electrodes; 1104 represents a conductive thin film; 1105 represents an electron-imitting portion formed by the forming process; 1113 represents a thin film formed by an activation process.

As the substrate 1101, various glass substrates such as, for example, quartz glass and soda-lime glass, various ceramic substrates such as alumina, or any of the above substrates having an insulating layer formed thereon can be used. have. The device electrodes 1102 and 1103 parallel to the substrate 1101 and provided against each other include conductive materials. For example, a metal material such as Ni, Cr, Au, Mo, W, Pt, Ti, Cu, Pd, and Ag, or alloys of these metals, otherwise metal oxides such as In ₂ O ₃ -SnO ₂ Or any of semiconductor materials such as polysilicon. These electrodes 1102 and 1103 can be easily formed by a combination of a film-forming technique such as vacuum-deposition and a patterning technique such as photolithography or etching, but any other method such as a printing technique can be used.

The shape of the electrodes 1102 and 1103 is suitably designed depending on the application of the electron-emissive device. In general, the spacing L between the electrodes is designed by selecting an appropriate value in the range of several hundred microseconds to several hundred micrometers. The most preferred range for display devices is from a few microns to several tens of microns. For the electrode thickness d, an appropriate value is selected in the range from several hundreds of micrometers to several micrometers.

The conductive thin film 1104 includes a fine particle film. This fine particle film is a film containing many fine particles (including masses of particles) as film-constituting members. From a microscopic point of view, the individual particles are generally present in the membrane at predetermined intervals, adjacent to each other or overlapping each other. One particle has a radius in the range of several milliseconds to several thousand milliseconds. Preferably, this radius is in the range from 10 kPa to 2000 kPa. The thickness of this film is appropriately designated in consideration of the following conditions. Prerequisites for the electrical connection to the device electrodes 1102 and 1103, conditions for the formation process to be described later, conditions for specifying the electrical resistance of the fine particle film itself to be described later as appropriate values, and the like. Specifically, the thickness of the film is specified in the range of several milliseconds to several thousand milliseconds, and more specifically, 10 milliseconds to 500 milliseconds.

Materials used for forming fine particle films include, for example, metals such as Pd, Pt, Ru, Ag, Au, Ti, In, Cu, Cr, Fe, Zn, Sn, Ta, W and Pb, Oxides such as PdO, SnO ₂ , In ₂ O ₃ , PbO and Sb ₃ O ₃ , borides such as HfB ₂ , ZrB ₂ , LaB ₆ , CeB ₆ , YB ₄ , TiC, ZrC, HfC, TaC Carbides such as SiC and WC, nitrides such as GdB4, TiN, ZrN and HfN, semiconductors such as Si, Ge, and carbon. Any suitable material (s) are suitably selected.

As described above, the conductive thin film 1104 is formed of a fine particle film, and the sheet resistance of the film is specified to fall within a range from 10 ³ to 10 ⁷ (dl / sq).

Since the conductive thin film 1104 is preferably connected to the device electrodes 1102 and 1103, they are arranged to overlap at one part with each other. In FIG. 7B, respective portions overlap from the bottom in order of the substrate 1101, the device electrodes 1102 and 1103, and the conductive thin film 1104. This overlapping order may be from the bottom, to the substrate 1101, the conductive thin film 1104, and the device electrodes 1102 and 1103.

Electron-emitting portion 1105 is a measured portion formed in a portion of conductive thin film 1104. The electron-emitting portion 1105 has higher resistive properties than the surrounding conductive thin film. This pitcher is formed by a forming process which will be discussed later with respect to the conductive thin film 1104. In some cases, particles having a radius of several milliseconds to several hundred milliseconds are arranged in the sectioned portion. Since it is difficult to accurately depict the actual position and shape of the electron-emitting portion, FIGS. 7A and 7B schematically illustrate the imaged portion. The thin film 1113 is preferably graphite monocrystalline, graphite polycrystalline, amorphous carbon, or a mixture thereof, and the thickness thereof is 500 GPa or less, more preferably 300 GPa or less.

Since it is difficult to accurately depict the actual position and shape of the thin film 1113, FIGS. 7A and 7B schematically illustrate this film. 7A shows this device where a portion of thin film 1113 has been removed.

The preferred basic structure of the surface-conductive emission type emitting device is as described below. In this embodiment, the device has the following configuration.

Substrate 1101 includes soda-lime glass, device electrodes 1102 and 1103, and a Ni thin film. The electrode thickness d is 1000 mm 3 and the electrode gap L is 2 m.

The main substance of the fine particle film is Pd or PdO. The thickness of the fine particle film is about 100 mm 3, and the width W thereof is 100 μm.

Next, a preferred method of manufacturing a flat surface-conducting emission type emitting device will be described with reference to FIGS. 8A to 8D, which are cross-sectional views showing a manufacturing process of a surface-conductive emission type emitting device. Note that the reference numerals are the same as those of Figs. 7A and 7B.

(1) First, as shown in FIG. 8A, device electrodes 1102 and 1103 are formed on the substrate 1101. In forming the electrodes 1102 and 1103, first, the substrate 1101 is thoroughly washed with detergent, pure water and organic solvent, and then the material of the device electrodes is deposited thereon. As the deposition method, film-forming techniques such as vacuum deposition and sputtering can be used.

Thereafter, patterning using photolithographic etching techniques is performed on the deposited electrode material. Thus, the device electrodes 1102 and 1103 shown in FIG. 8A are formed.

(2) Next, as shown in FIG. 8B, a conductive thin film 1104 is formed.

In the formation of the conductive thin film 1104, an organic metal solvent is first applied to the substrate of FIG. 8A, and then the applied solvent is dried and sintered to form a fine particle film. Thereafter, the fine particle film is patterned into a predetermined shape by the photolithography etching method. This organometallic solvent means a solvent of an organometallic compound containing a material of fine particles, and is used for forming a conductive thin film, and in this embodiment, Pd is a main component thereof. However, in this embodiment, the application of the organometallic solvent is made by dipping, and any other method such as a spinner method and a spraying method can be used.

As the film-forming method of the conductive thin film 1104 made of fine particles, the application of the organometallic solvent used in this embodiment is carried out by a vacuum deposition method, a sputtering method or a chemical vapor-phase accumulation method. alternative methods such as accumulation method).

(3) Then, as shown in FIG. 8C, a suitable voltage is applied between the device electrodes 1102 and 1103 from the power supply 1110 for the forming process, and then the forming process is performed to carry out the electron-already. The casting portion 1105 is formed. The formation process here involves the electrical of the conductive thin film 1104 formed of a fine particle film as shown in FIG. 8B to properly destroy, deform or deteriorate a portion of the conductive thin film 1104. As an electrical energization, this film is modified to have a structure suitable for electron emission. In the conductive thin film 1104, this portion (electron-imitting portion, 1105), which has been changed for electron emission, has a suitable pitcher in the thin film. Comparing this thin film 1104 with the electron-emitting portion 1105 with that thin film before the forming process, the electrical resistance measured between the device electrodes 1102 and 1103 was greatly increased.

The electrification method in the forming process will be described in more detail with reference to FIG. 9 which shows an example of a suitable voltage waveform applied from the forming power source.

Preferably, in the case of forming the fine particle film of the conductive thin film, a pulse-type voltage is used. In this embodiment, as shown in Fig. 9, a triangular-wave pulse having a pulse width T1 is applied continuously with a pulse interval T2. Upon application, the wave peak value Vpf of the triangular-wave pulses is continuously increased.

In addition, a monitor pulse Pm is inserted between the triangular-wave pulses at appropriate intervals to monitor the electron-emitting portion 1105 formation state, and the current flowing at this insertion is measured by a galvanometer.

In this embodiment, in a 10 ⁻⁵ Torr vacuum atmosphere, the pulse width T1 is specified to 1 msec; Pulse interval T2 is specified at 10 msec. The peak value Vpf of the wave is increased by 0.1 V for each pulse. Each time a triangular-wave of five pulses is applied, a monitor pulse Pm is inserted. To avoid adverse effects on the formation process, the Vpm of the monitor pulse is specified as 0.1V. When the electrical resistance between the device electrodes 1102 and 1103 becomes 1 × 10 ⁶ kA, that is, when the current measured by the galvanometer 1111 when the monitor pulse is applied becomes 1 × 10 ⁻⁷ A or less, Charging of the forming process is stopped.

Note that the formation method is preferred for the surface-conductive emission type emitting device of the present embodiment. In the case of changing the design of the surface-conducting emission type emitting device, for example, the material or thickness of the fine particle film, or the device electrode spacing L, the conditions for electrification may be desirably changed according to the change of the device design. Can be.

(4) Next, as shown in FIG. 8D, an appropriate voltage is applied between the device electrodes 1102 and 1103 from the activation power supply 1112, so that an activation process for improving the electron-emitting characteristic is performed. . The activation process here comprises the electron-emissive portion 1105 shown in FIG. 8C formed by the forming process under suitable condition (s) to deposit carbon or carbon compound material around the electron-emissive portion 1105. ) (In FIG. 8D, the deposited carbon or carbon compound material is shown as material 1113). Comparing this electron-emissive portion 1105 with that before the activation process, the emission current is generally 100 times or more at the same applied voltage.

This activation is made by periodically applying a voltage pulse in a 10 ⁻² or 10 ⁻⁵ Torr vacuum atmosphere to accumulate carbon or carbon compound derived primarily from the organic compound (s) present in the vacuum atmosphere. This accumulated material 1113 is any one of graphite monocrystallin, graphite polycrystallin, amorphous carbon or a mixture thereof. The accumulated material 1113 has a thickness of 500 kPa or less, more preferably 300 kPa or less.

The charging method in this activation process will be described in more detail with reference to FIG. 10A which shows an example of a suitable voltage waveform applied from the activation power supply 1112. In this example, the square-wave voltage Va is 14V; Pulse width T3 at 1 msec; And pulse interval T4 is specified by 10 msec. Note that the above charging conditions are suitable for the surface-conductive emission type emitting device of the present embodiment. When changing the design of the surface-conducting emission type emitting device, the charging conditions are preferably changed in accordance with the device design change.

In FIG. 8D, reference numeral 1114 denotes an anode connected to a direct current (DC) high voltage power supply 1115 and a galvanometer 1116 to capture the emission current Ie emitted from the surface-conductive emission type emitting device. electrode). When the substrate 1101 is bonded to the display panel before the activation process, an Al film on the fluorescent surface of the display panel is used as the anode electrode 1114. While applying a voltage from the activation power supply 1112, the galvanometer 1116 measures the emission current Ie and monitors the activation process to control the operation of the activation power supply 1112. 10B shows an example of the emission current Ie measured by the galvanometer 1116.

When the application of the pulse voltage from the activating power supply 1112 begins in this manner, the emission current Ie increases over time, gradually reaching saturation, and then almost no increase at all. At the substantial saturation point, the application of voltage from the activation power supply 1112 is stopped and the activation process is stopped.

Note that the above charging conditions are preferable for the surface-conductive emission type emitting device of this embodiment. When changing the design of the surface-conducting emission type emitting device, the conditions can be changed desirably according to the change of the device design.

As described above, a surface-conductive emission type emitting device as shown in FIG. 8E is manufactured.

Stepped Surface-Conductive Emission Type Emitting Devices

Next, another typical structure of the surface-conducting emission type emitting device in which the electron-imitting portion or a peripheral portion thereof is formed of a fine particle film, that is, a step-type surface-conducting emission type emitting device will be described. will be.

11 is a schematic cross-sectional view showing the basic structure of a stepped surface-conducting emission type emitting device.

Referring to Fig. 11, reference numeral 1201 denotes a substrate; 1202 and 1203 represent device electrodes; 1206 represents a step-forming member that makes a height difference between the electrodes 1202 and 1203; 1204 represents a conductive thin film using a fine particle film; 1205 represents an electron-imitting portion formed by the forming process; And 1213 represents a thin film formed by the activation process.

The difference between the stepped surface-conducting emission type emitting device and the flat surface-conducting emission type emitting device described above is that one of the device electrodes (1202 in this example) is provided on the step-forming member 1206. And the conductive thin film 1204 covers the side of the step-forming member 1206. The device spacing L of FIGS. 7A and 7B is designated as the height difference Lst corresponding to the height of the step-forming member 1206 in this structure. Note that the substrate 1201, the device electrodes 1202 and 1203, and the conductive thin film using the fine particle film may include the materials given in the description of the flat surface-conductive emission type emitter device. In addition, the step-forming member 1206 includes an electrically insulating material such as SiO ₂ .

Next, a method of manufacturing a stepped surface-conducting emission type emitting device will be described with reference to Figs. 12A to 12F, which are cross-sectional views showing the manufacturing processes thereof. In these figures, reference numerals of respective parts are the same as those of FIG. 10.

(1) First, as shown in FIG. 12A, a device electrode 1203 is formed on the substrate 1201.

(2) Next, as shown in Fig. 12B, an insulating layer 1206 for forming a step-forming member is deposited. This insulating layer 1206 may be formed, for example, by accumulation of SiO ₂ or by a sputtering method, but this insulating layer may be formed by a film-forming method such as a vacuum deposition method or a printing method.

(3) Next, as shown in FIG. 12C, a device electrode 1202 is formed on the insulating layer 1206.

(4) Next, as shown in FIG. 12D, a portion of the insulating layer 1206 of FIG. 12C is removed using, for example, an etching method to expose the device electrode 1203.

(5) Next, as shown in Fig. 12E, a conductive thin film 1204 is formed using a fine particle film. In this formation, a film-forming technique is used, such as an applying method, similar to the flat device structure described above.

(6) Next, a forming process similar to the flat device structure is performed to form the electron emitting portion 1205. (A formation process similar to that described using FIG. 8C may be performed).

(7) Next, an activation process similar to the flat device structure is performed to deposit carbon or carbon compound around the electron-emisting portion (activation process similar to that described using FIG. 8D can be performed). .

As described above, the stepped surface-conductive emission type emitting device shown in Fig. 12F is manufactured.

Characteristics of surface-conductive emission type emitter devices used in display devices

The structure and manufacturing method of the flat surface-conducting emission type emitting device and those of the stepped surface-conducting emission type emitting device are as described above. Next, the characteristics of the emitting device used in the display apparatus will be described below.

Fig. 13 shows the characteristics of [imitation current Ie] versus [device voltage (i.e., voltage to be applied to this device) Vf] and [device current If] vs [device application voltage Vf] of this device used in the display device of this embodiment. Characteristics. Note that compared to the device current If, the emission current Ie is so small that it is difficult to show the emission current by the same measurement as for the device current If. In addition, these characteristics change due to changes in design variables such as the size or shape of the device. For these reasons, the two lines in the graph of FIG. 13 are each given in arbitrary units.

Regarding the emission current Ie, the device used in the display device has three characteristics as follows.

First, if a predetermined level or more, referred to as the threshold voltage Vth, is applied to the device, the emission current Ie increases sharply, but at a voltage lower than the threshold voltage Vth, the emission current Ie is hardly detected. That is, for the emission current Ie, the device has a nonlinear characteristic based on the pronounced threshold voltage Vth.

Second, the emission current Ie changes in accordance with the device applied voltage Vf. Accordingly, the emission current Ie can be controlled by the change of this device voltage Vf.

Third, the emission current Ie is quickly output in response to the application of the device voltage Vf to the surface-conductive emission type emitting device. Thus, the electrical charge amount of electrons to be emitted from the device can be controlled by changing the application period of the device voltage Vf.

Surface-conductive emission-type emitting devices having the above three characteristics are preferably applied to display devices. For example, in a display apparatus having a large number of the devices provided according to the number of pixels of the display screen, if the first characteristic is utilized, display by continuous scanning of the display screen is possible. This means that a voltage lower than the threshold voltage Vth is applied to the unselected device, while the threshold voltage Vth or more is appropriately applied to the driven device. In this way, continuously changing the drive device enables display by continuous scanning of the display screen.

In addition, the emission luminance can be controlled by utilizing the second or third characteristic, which enables a multi-gradation display.

Multi-electronic source structure with many devices wired in simple matrix

Next, the structure of a multi-electron source having the above-mentioned surface-conductive emission type emitting devices arranged on a substrate with simple-matrix wiring will be described below.

3 is a plan view of a multi-electronic source used in the display panel of FIG. 2. On the substrate 1011 there are surface-conductive emission type emitting devices such as those shown in FIGS. 7A and 7B. These devices are arranged in a simple matrix form with column-oriented wiring 1013 and row-direction wiring 1014. At the intersection of the wirings 1013 and 1014, an insulating layer, not shown, is formed between these wirings to maintain electrical separation.

4 is a cross-sectional view taken along the line BB ′ of FIG. 3.

A multi-electron source having such a structure includes column- and row-direction wirings 1013 and 1014, inter-electrode insulating layers not shown, device electrodes, and surface-conductive emission type emitting on a substrate. By forming the conductive thin films of the devices, and then supplying electricity to the respective devices through these column- and row-direction wirings 1013 and 1014 to perform the forming process, which will be described later, and the activation process, which will also be described later. Note that it is manufactured.

Fig. 14 is a block diagram showing a schematic arrangement of driving circuits for performing television display based on the television signal of the NTSC scheme. Referring to FIG. 14, the display panel 1701 corresponds to the display panel described above. This panel is manufactured and operated in the manner as described above. The scanning circuit 1702 scans the display lines. The control circuit 1703 generates signals to be input to the scanning circuit and the like. Shift register 1704 shifts data in units of lines. The line memory 1705 inputs one-line data from the shift register to the modulation signal generator 1707. A sync signal separation circuit 1706 separates the sync signal from the NTSC signal.

The function of each component of FIG. 14 will be described in detail below.

The display panel 1701 is connected to an external electrical circuit through the terminals Dx1 to DxM and Dy1 to DyN and the high-voltage terminal Hv. Scanning signals for successively driving multi-electron sources in the display panel 1701, ie, cold cathode devices wired in an M × N matrix in units of lines (in n device units), are provided at terminals Dx1 through DxM. Is approved. Modulation signals are applied to terminals Dy1 to DyN to control the electron beams output from the n devices corresponding to one line selected by the scanning signals. For example, a DC voltage of 5 kV from the DC voltage source Va is applied to the high-voltage terminal Hv. This voltage is an accelerating voltage to give enough energy to excite fluorescent materials to the electron beams output from the multi electron source.

The scanning circuit 1702 will be described next. This circuit incorporates the M switching elements indicated by reference numerals S1 to SM in FIG. Each switching element serves to select one of an output voltage from the DC voltage source Vx and a ground level of 0V, and is electrically connected to a corresponding one of the terminals Dx1 to DxM of the display panel 1701. The switching elements S1 to SM operate based on the control signal TSCAN output from the control circuit 1703. In practice, this circuit can be easily formed in combination with switching elements such as FETs. As the drive voltage to be applied to the non-scanned device is specified to be the electron emission threshold voltage Vth or less, the DC voltage source Vx is based on the characteristics of the electron-emissive device of FIG. 13 to output a constant voltage. Is specified.

The control circuit 1703 serves to harmonize the operations of the respective components to perform appropriate display based on the external input image signal. The control circuit 1703 generates control signals TSCAN, TSFT, TMRY for each component based on the sync signal TSYNC sent from the sync signal separation circuit 1706, which will be described next. The sync signal separation circuit 1706 is a circuit for separating the sync signal component and the luminance signal component from an externally input NTSC television signal. As is known, this circuit can be easily formed using a frequency separation (filter) circuit. The sync signal separated by the sync signal separation circuit 1706 consists of vertical and horizontal sync signals, as is known. In this case, the sync signal is shown as signal TSYNC in FIG. 14 for convenience of explanation. The luminance signal component of the image separated from the television signal is represented as the signal DATA for explanatory convenience. This signal is input to the shift register 1704.

The shift register 1704 performs serial / paraallel conversion for units of lines of an image on a signal DATA input in series in a time-series manner. The shift register 1704 operates based on the control signal TSFT sent from the control circuit 1703. In other words, the control signal TSFT is a shift clock for the shift register 1704. The one-line data (corresponding to the drive data for n electron-emitting devices) obtained by the serial / parallel conversion is output from the shift register 1704 as N signals ID1 to IDN.

Line memory 1705 is a memory for storing 1-line data for the required time period. The line memory 1705 suitably stores the contents of the signals ID1 to IDN in accordance with the control signal TMRY sent from the control circuit 1703. The stored contents are output as data I'D1 to I'DN and input to the modulated signal generator 1707.

The modulated signal generator 1707 is a signal source for performing appropriate driving / modulation for each e-emisting device in accordance with each of the image data I'D1 to I'DN. Output signals from the modulated signal generator 1707 are applied to the electro-emissive devices 1015 in the display panel 1701 via terminals Dy1 through DyN.

The surface-conductive emission type emitting device according to the present embodiment has the following basic characteristics with respect to the emission current Ie, as described above with reference to FIG. A certain threshold voltage Vth (8V in the surface-conductive emission type emitting device of the embodiment described later) is specified for the electron emission. Each device emits electrons only when a voltage equal to or greater than the threshold voltage Vth is applied. In addition, the emission current Ie changes with the change of the voltage which is equal to or more than the electron emission threshold voltage Vth, as shown by the graph of FIG. Clearly, when a pulsed voltage is applied to this device, if this voltage is lower than the electron emission threshold voltage Vth, electrons are not emitted. However, if this voltage is equal to or greater than the electron emission threshold voltage Vth, the surface-conductive emission type emitting device emits an electron beam. In this case, the intensity of the output electron beam can be controlled by changing the peak value Vm of this pulse. In addition, the total charge amount of the electron beam output from the device can be controlled by the change of the pulse width Pw.

Therefore, as a scheme for modulating the output from each electron-emitting device according to the input signal, a voltage modulation scheme, a pulse width modulation scheme, or the like can be used. In implementing the voltage modulation scheme, a voltage modulation circuit can be used as the modulation signal generator 1707 to generate a voltage pulse having a certain length in accordance with the input data and modulate the peak value of the voltage pulse. In executing the pulse width modulation scheme, a pulse width modulation circuit for generating a voltage pulse having a constant peak value according to the input data and modulating the width of the voltage pulse can be used as the modulation signal generator 1707.

The shift register 1704 and the line memory 1705 may be a digital type or an analog type. That is satisfactory if the image signal is serial / parallel converted and stored at a predetermined rate.

If the components are of digital signal type, the output signal DATA from the sync digital signal separation circuit 1706 must be converted into a digital signal. For this purpose, an A / D converter will be connected to the output terminal of the sink signal separation circuit 1706. Somewhat different circuits are used for the modulated signal generator depending on whether the line memory 1705 outputs a digital signal or an analog signal. More specifically, in the case of a voltage modulation scheme using a digital signal, for example, a D / A conversion circuit is used as the modulation signal generator 1707, and if necessary, such as an amplification circuit is added thereto. In the case of a pulse width modulation scheme, for example, a circuit composed of a combination of a high speed oscillator, a counter for counting the frequency of the signal output from the oscillator, and a comparator for comparing the output value from the counter and the output value from the memory is provided. It is used as a modulated signal generator 1707. This circuit may include, if necessary, an amplifier that amplifies the voltage of the pulse width modulated signal output from the comparator to a drive voltage for the electro-emissive device.

In the case of a voltage modulation scheme using an analog signal, an amplification circuit using an operational amplifier and the like can be used as the modulation signal generator 1707 and, if necessary, a shift level circuit and the like can be added thereto. Can be. In the case of a pulse width modulation scheme, for example, a voltage-controlled oscillator (VCO) can be used and, if necessary, amplifying the output from this oscillator to the driving voltage for the electro-emissive device. Amplifiers can be added there.

In the image forming apparatus of this embodiment, which may have one of the above arrangements, electrons are emitted when applied to the respective electron-emissive devices through the external terminals Dx1 to DxM and Dy1 to DyN. High voltage is applied to the metal backside 1019 or transparent electrode, not shown, through the high-voltage terminal Hv to accelerate the electron beams. The accelerated electrons collide with the fluorescent film 1018 to cause it to emit light, whereby an image is formed.

The image display apparatus of the above arrangement is an example of an image forming apparatus to which the present invention can be applied. Various modifications and variations of the present invention can be made within the spirit and scope of the present invention. Although a signal based on the NTSC scheme is used as the input signal, this input signal is not limited to this. For example, PAL scheme and SECAM scheme can be used. In addition, a TV signal (high-definition TV, such as MUSE) scheme that uses a larger number of scanning lines than these schemes may be used.

EXAMPLE

The invention will be further described below with reference to the embodiments.

In each of the embodiments described below, the multi-electron source is used to provide N x M (N = 3,072, M = 1,024) surface-conductive emission type emitter devices with M column-directional wirings and N row-directional wirings. It is formed by wiring with the matrix used, each of which has an electron-emisting portion of the conductive fine particle film between the electrodes as described above (see Figs. 2 and 3).

In each of the embodiments described below, as shown in FIG. 6, the front plate 1017 has a fluorescent film 1018, in which fluorescent materials of respective colors are arranged in a row direction (Y direction). Has a stripe shape (stripes) and black conductive members 1010 are perpendicular to the stripes as well as between the stripes of fluorescent materials of each color to separate the pixels in the column and row directions. It is also arranged in the (X direction).

(First embodiment)

In the first embodiment, an image display apparatus using the spacers 1020 described with reference to FIGS. 1 and 2 is manufactured. The first embodiment will be described in detail below with reference to FIGS. 1 and 2.

The spacer 1020 used in the first embodiment was manufactured in the following manner.

(1) Glass of the same kind as the glass for the front plate 1017 and the substrate 1011 was used, cut and polished to 20 mm in length, 5 mm in height, and 0.2 mm in thickness. The resulting glass was used as the insulating member 1.

(2) As the high-resistance film 11, a Cr-Al alloy nitride film was formed on the surface of the insulating member 1. The high-resistance film 11 was formed to have a thickness of 200 nm using Cr and Al treatment in a nitride gas atmosphere simultaneously with reactive sputtering. The sheet resistance of this high-resistance film 11 is about 10 ⁹ kPa / sq.

(3) On the insulating member 1 covered with the high-resistance film 11, the low-resistance films 21a and 21b and the protective film 23 are on the front plate 1017 side and the substrate 1011 side. It was formed continuously by RF-sputtering Ti and Pt targets at a thickness of 50 kPa to 2000 kPa on the joining surfaces 3a and 3b and on the side of the front plate side. The remaining portions except the film-forming portions were covered with a metal mask. As the layer below the Pt layer, a 50 mm thick Cr layer or a 50 mm thick Ta layer was formed instead of the Ti layer.

The display panel was assembled by the following process using the spacer 1020 manufactured in the above manner.

(1) a bonding material 31 of conductive molten glass (line width: 250 μm, height: 200 μm), including a conductive filler coated with gold, through the metal backside 1019, In order to border each spacer 1020 to a part of an area (line width: 300 µm) extending in the column direction (X direction) of the black conductive member 1010 of the fluorescent film 1018 on the front plate 1017 side. Is approved.

(2) The spacer 1020 was disposed in the region of the front plate 1017 to which the bonding material 31 was applied, and the spacer 1020 was applied at 400 ° C. to 500 ° C. to attach the spacer 1020 to the front plate 1017 side. It was sintered for 10 minutes or more in air and was also electrically connected to the metal backside 1019. In this case, the spacer 1020 was satisfactorily disposed with respect to the front plate 1017. In particular, the inclination (upright angle) of the spacer 1020 relative to the surface of the front plate 1017 was adjusted to fall within the 90 ° ± 5 ° range.

(3) a substrate on which conductive thin films of column- and row-direction wirings 1013 and 1014, inter-electrode insulating layers (not shown), device electrodes, and surface-conductive emission-type emitting devices were formed thereon ( 1011) is satisfactorily positioned and secured to rear plate 1015.

Column- and row-directional wirings 1013 and 1014 were formed by burning a silver paste containing Ag and glass components after printing.

As shown in FIG. 20, each column-direction wiring 1013 has a shape protruding to a portion where the row-direction wiring 1014 and the insulating layer 1099 exist.

(4) The front plate 1017 to which the spacers 1020 are attached and the back plate 1015 to which the substrate 1011 is fixed are made to face each other through the side walls 1016. In this case, the bonding end of each spacer 1020 on which the low-resistance film 21b was formed was disposed on the column-direction wirings 1013 on the back plate 1015 side, and the back plate 1015 and the front plate. 1017 and sidewalls 1016 were fixed as shown in FIGS. 1, 2, and 20.

Bonding portions between the substrate 1011 and the back plate 1015, between the back plate 1015 and the sidewalls 1016, and between the front plate 1017 and the sidewalls 1016 are coated with molten glass, not shown. It became. The resulting structure was sintered to seal the components for 10 minutes or more in air at 400 ° C to 500 ° C. In this case, the back plate 1015 and the front plate 1017 were satisfactorily arranged to make the fluorescent materials of the respective colors on the front plate 1017 correspond with the cold cathode devices 1012 on the substrate 1011 with each other. .

The sealed container constituting the display panel was completed by the above process.

The sealed container completed by the process was emptied by a vacuum pump through an outlet pipe, not shown, to obtain sufficient vacuum. Thereafter, power is supplied to the terminals Dx1 to DxM and Dy1 to DyN, the column-directional wirings 1013, and the row-directional wirings 1014 to perform the forming process and the activation process, whereby An electronic source was produced.

The discharge pipe, not shown, was heated and welded using a gas burner to seal the envelope (closed container) in a vacuum on the order of 10 ^-6 Torr.

Finally, gettering was performed to maintain the vacuum after sealing.

In the image display apparatus using the display panel completed in the above process shown in Figs. 1 and 2, in order to cause these devices to emit electrons, an external terminal from a signal generating apparatus in which scanning signals and modulation signals are not shown Were applied to the respective cold cathode devices (surface-conduction emission type emitting devices) via Dx1 to DxM and Dy1 to DyN. A high voltage was applied to the metal backside 1019 through the high-voltage terminal Hv to accelerate the emitted electron beams and cause these electrons to collide with the fluorescent film 1018. As a result, the fluorescent materials of each of the colors (R, G and B in FIG. 6) were excited to emit light, thereby displaying an image. The voltage Va to be applied to the high-voltage terminal Hv was specified as 3 kV to 10 kV, and the voltage Vf to be applied between each column-directional wiring 1013 and each row-direction wiring 1014 was designated as 14V.

In this case, the emission point columns were formed two-dimensionally at equal intervals, including the emission points formed by the electrons emitted by the cold cathode devices 1012 near the spacers 1020. As a result, a vivid color image with good color reproduction characteristics could be displayed. This indicates that the formation of spacers 1020 did not create any electric field disturbances affecting the trajectory of the electrons.

An embodiment using spacers 1020 without protruding layer 23 is also one of the embodiments of the present invention, and the effects as described above can also be obtained. However, the first embodiment in which the protruding layer 23 is formed on the spacer 1020 is more desirable to prevent distortion of the display image near the spacer 1020.

An embodiment in which the low-resistance film 21b on the side of the substrate 1011 having the cold cathode devices 1012 is formed of a side portion (height: 0.3 mm) of the spacer 1020 is also one of the embodiments of the present invention. And effects as described above can be obtained. However, the first embodiment of FIGS. 1 and 19 is more preferred to prevent distortion of the display image near the spacer 1020 caused by the shift of the electron beam in a direction away from the spacer 1020.

In the first embodiment, the spacer 1020 is adjacent to the substrate 1011 through a soft material at atmospheric pressure applied when emptying the sealed container. Compared to the case where the display panel is assembled using the bonding material 31 on both the front plate 1017 side and the substrate 1011 side, this spacer can be more reliably prevented from damage and tripping at the bonded portion. . In addition, this spacer is electrically connected to the substrate 1011 side more securely. This makes the assembly of closed containers easy and increases the yield.

(2nd Example)

In the first embodiment, as the protruding layer 23, a silicon nitride film (thickness: 500 nm, height: 0.3 mm) serving as an insulating film was used. As a result, the image could be displayed similarly to the first embodiment.

As described above, according to the present invention, an image forming apparatus having spacers excellent in fixing the strength inside the apparatus can be provided.

In particular, an image forming apparatus may be provided having spacers fixed on the image forming member but adjacent to the member facing the image forming member and which are excellent in fixing the strength inside the apparatus.

In addition, a method of manufacturing an image forming apparatus can be provided, in which the arrangement of the spacers can be facilitated in assembling the image forming apparatus because only one end of each spacer is adjacent.

According to this manufacturing method of the present invention, these spacers are disposed between the image forming member and the member facing the image forming member, and are fixed only to this image forming member. This produces the following advantages.

If the spacers are secured to both the image forming member and the member facing the image forming member, the mechanical and electrical connection between the spacers and both of the image forming member and the member facing the image forming member may cause the spacers to be imaged. It is performed simultaneously by pressing at a predetermined pressure toward the forming member and the member facing the image forming member. In order to press these spacers at a predetermined pressure, mechanical accuracy of device fabrication is required because the surfaces of the image forming member and the member facing the image forming member must be parallel and the heights of the spacers must be uniform. Also, in order to simultaneously fix the spacers to both the image forming member and the member facing the image forming member, a higher pressure is required, which causes an increase in the cost of manufacturing the device.

According to the invention, the spacers are fixed to the image forming member in order to more reliably achieve a mechanical and electrical connection between the spacers and the image forming member and to reduce the pressure on the spacer when the spacers are fixed. Since the spacers are not fixed simultaneously to the member facing the image forming member, non-uniformity of pressure to the spacers is not caused due to warp of the image forming member. Also, even if the image forming member is bent, it is convenient for the mechanical parts pressing the spacers to be divided into a plurality of sections relative to the area of the image forming member so that uniformity of pressure to the spacers can be achieved. something to do.

Further, according to the present invention, the spacers disposed between the image forming member and the member facing the image forming member are first fixed to the image forming member and in contact with the member facing the image forming member. The interior of the image display panel is emptied so that electrical contact between the spacers and the member facing the image forming member is more secure. Thus, the degree of parallelism and the uniformity of the spacer heights on the surfaces of the image forming member and the member facing the image forming member can be degraded.

For conductive spacers, errors in charge-up of the spacer surface, electrical connections at the connecting portion of the spacer can be reduced.

The number of factors shifting the electron trajectory near the spacer can be reduced.

Since the trajectory of the electron beam is not shifted well, an image forming apparatus capable of displaying a clear image with good color reproduction without luminance irregularity or color misregistration can be obtained.

Apparently, many various embodiments of the present invention can be made without departing from the spirit and scope of the invention, and it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims. It should be understood.

Claims (58)

In the image forming apparatus, An electron source having a plurality of electron-emitting devices, an image forming member for forming an image according to irradiation of electrons emitted by the electron-emitting devices, and the image forming member and the image forming And spacers arranged between members facing the member, wherein the spacers are in contact with the member fixed to the image forming member and facing the image forming member. According to claim 1, And said member facing said image forming member comprises a substrate on which a plurality of electron-emitting devices are arranged, said spacers being in contact with said substrate through flexible members. According to claim 1, The electron-emissive devices are connected by wires, the member facing the image forming member comprises a substrate on which the plurality of electron-emissive devices are arranged, and the spacers are interconnected via flexible members. And an image forming apparatus in contact with the field. According to claim 1, The plurality of electron-emitting devices are wired in a matrix form through a plurality of column-directional wires and a plurality of row-directional wires, and the member facing the image forming member is configured by And a substrate arranged thereon, wherein the spacers are in contact with the column-directional wires or the row-directional wires through flexible members. The method of claim 4, wherein And the spacers are rectangular spacers, and the junction surface of the column-directional wires or the row-directional wires comprises corrugations. According to claim 1, And the spacers are fixed to the image forming member by welding using a bonding material. According to claim 1, And said spacers are in contact with a member facing said image member through flexible members, each of said flexible members being a member that is softer than said member being in contact with said spacers. According to claim 1, The spacers are in contact with the member facing the image forming member through the flexible members, wherein each of the flexible members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. An image forming apparatus. According to claim 1, And the electro-emissive devices are cold cathode devices. The method of claim 9, And each of said cold cathode devices is a device comprising a conductive film having an electron-emisting portion between electrodes. 10. An image forming apparatus according to claim 9, wherein each of said cold cathode devices is a surface-conductive emission type emitting device. According to claim 1, And the spacer is a spacer having conductivity. The method of claim 12, And the spacer has a sheet resistance in the range of 10 ⁵ kW / sq to 10 ¹² kW / sq. The method of claim 12, The plurality of electron-emitting devices are connected by wires, the member facing the image forming member includes a substrate on which the plurality of electron-emitting devices are arranged, and the spacers are flexible And an electrical connection with said wirings via electrically conductive members. The method of claim 14, And each of the flexible conductive members is a softer member than the spacers and the wirings in contact with each other. The method of claim 14, Each of the flexible conductive members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. The method of claim 14, Each of said spacers is fixed to an acceleration electrode for accelerating electrons emitted by said electron-emitting devices disposed on said substrate and electrically connected to said acceleration electrode. The method of claim 17, And each of the spacers is fixed to the acceleration electrode through a noble metal film. The method of claim 17, Each of said spacers is fixed to said acceleration electrode by welding using a bonding material. The method of claim 12, The plurality of electron-emissive devices are wired in a matrix form through a plurality of column-directional wires and a plurality of row-directional wires, wherein the member facing the image forming member is arranged by the electron-emitting devices. And a substrate, wherein the spacers are in contact with the column-direction wires or the row-direction wires via a flexible conductive member and are electrically connected to the wires. The method of claim 20, And wherein each of the flexible conductive members is a softer member than the spacers and the wirings in contact with each other. The method of claim 20, Each of the flexible conductive members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. The method of claim 20, And each of said spacers is fixed to an acceleration electrode for accelerating electrons emitted by said electron-emitting devices disposed on said substrate and electrically connected to said acceleration electrode. The method of claim 23, wherein Each of the spacers is fixed to the acceleration electrode through a noble metal film. The method of claim 23, wherein Each of the spacers is fixed to the acceleration electrode by welding using a bonding material. The method of claim 20, And the spacers are rectangular spacers, and the junction surface of the column-directional wires or the row-directional wires comprises corrugations. The method of claim 12, And the electro-emissive devices are cold cathode devices. The method of claim 27, And each of said cold cathode devices is a device comprising a conductive film having an electron-emisting portion between electrodes. The method of claim 27, And each of said cold cathode devices is a surface-conductive emission type emitting device. An electron source having a plurality of electron-emitting devices, an image forming member for forming an image according to irradiation of electrons emitted by the electron-emitting devices, and the image forming member and the image forming A method of manufacturing an image forming apparatus comprising spacers arranged between members facing a member, the method comprising: Securing the spacers to the image forming member; Contacting said spacers with said member facing said image forming member. The method of claim 30, The member facing the image forming member includes a substrate on which the plurality of electronic imaging devices are arranged, and contacting the spacers to the member includes: Contacting the spacers with the substrate on which the plurality of electron-emitting devices are arranged via flexible members. The method of claim 30, The plurality of electron-emitting devices are connected by wires, and the member facing the image forming member includes a substrate on which the plurality of electron-emitting devices are arranged, the contacting spacers with the member. The steps are: Contacting the spacers with the wirings through flexible members. The method of claim 30, The plurality of electron-emissive devices are wired in a matrix form through a plurality of column-direction wires and a plurality of row-direction wires, and the member facing the image forming member is arranged by the plurality of electron emitting devices. And a step of bringing the spacers into contact with the member, the contacting of the spacers with the column-direction wirings or the row-direction wirings through flexible members. . The method of claim 33, wherein And said spacers are rectangular spacers, and said joining surfaces of said column-oriented wirings or said row-directional wirings comprise corrugations. The method of claim 30, Fixing the spacers to fixing the spacers to the image forming member by welding using a bonding material. The method of claim 30, The spacers are brought into contact with a member facing the image forming member through the flexible members, wherein each of the flexible members is a softer member than the spacer and the member being contacted. Manufacturing method. The method of claim 30, And the spacers are in contact with the member facing the image forming member through the flexible members, wherein each of the flexible members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. Method of manufacturing the forming apparatus. The method of claim 30, And said electron-emitting devices are cold cathode devices. The method of claim 38, wherein Wherein each of the cold cathode devices is a device comprising a conductive film having an electron-emisting portion between the electrodes. The method of claim 38, wherein Wherein each of the cold cathode devices is a surface-conductive emission type emitting device. The method of claim 30, And each of the spacers is a conductive spacer. 42. The method of claim 41 wherein Wherein each of said spacers has a sheet resistance within a range of 10 ⁵ kW / sq to 10 ¹² kW / sq. 42. The method of claim 41 wherein The plurality of electron-emitting devices are connected by wires, the member facing the image forming member includes a substrate on which the plurality of electron-emitting devices are arranged, and the spacers with the member. And the step of contacting electrically connects the spacers to the wirings through a flexible conductive member, and contacting the spacers with the wirings. The method of claim 43, And wherein each of the flexible conductive members is a member that is softer than the respective spacers or the respective wirings to be in contact with each other. The method of claim 43, And wherein each of the flexible conductive members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. The method of claim 43, The fixing of the spacers may include electrically connecting the spacers to an acceleration electrode for accelerating electrons emitted by the electron-emitting devices arranged on the substrate, and fixing the spacers to the acceleration electrode. Method of manufacturing an image forming apparatus comprising a. 47. The method of claim 46 wherein And fixing the spacers to the acceleration electrode comprises fixing the spacers to the acceleration electrode through a noble metal film. 47. The method of claim 46 wherein And fixing the spacers to the acceleration electrode comprises fixing the spacers to the acceleration electrode by welding using a bonding material supplied on the acceleration electrode. 42. The method of claim 41 wherein The electron-emitting devices are electron-emitting devices wired in a matrix form through a plurality of column-direction wires and a plurality of row-direction wires, and the member facing the image forming member is the electron-emitting device And a substrate in which the spacers are arranged, and contacting the spacers with the member electrically connects the spacers to the column-direction wirings or the row-direction wirings through a flexible conductive member, And contacting the column-directional wires or the row-directional wires. The method of claim 49, Wherein each of the flexible conductive members is a softer member than each of the spacers or each of the wirings to be in contact with each other. The method of claim 49, And wherein each of the flexible conductive members is a member made of a material selected from the group consisting of a noble metal and an alloy of the noble metal. The method of claim 49, The fixing of the spacers is: Electrically connecting said spacers to an acceleration electrode for accelerating electrons emitted by said electron-emitting devices arranged on said substrate, and fixing said spacers to said acceleration electrode. Method of manufacturing the forming apparatus. The method of claim 52, wherein And fixing the spacers to the acceleration electrode comprises fixing the spacers to the acceleration electrode through a noble metal film. The method of claim 52, wherein And fixing the spacers to the acceleration electrode comprises fixing the spacers to the acceleration electrode by welding using a bonding material supplied to the acceleration electrode. The method of claim 49, And said spacers are rectangular spacers, and said joining surface of said column-oriented wirings or said row-directional wirings comprises corrugations. 42. The method of claim 41 wherein And said electron-emitting devices are cold cathode devices. The method of claim 56, wherein And said cold cathode device is a device comprising a conductive film having an electron-imitting portion between electrodes. The method of claim 57, And the cold cathode device is a surface-conductive emission type emitting device.